ISLAMABAD, Pakistan (CNN) -- The United States is suspected in a missile strike that killed at least 15 people Monday in western Pakistan, a Pakistani official said.

At least seven people were also injured in the attack near the Afghan border about 9 a.m. Monday, according to an official in Kurram agency. The death toll is expected to rise, intelligence sources said.

Drones reportedly could still be heard overhead, discouraging people from digging victims out of the debris. Area residents said they heard two unmanned drones overhead before the attack.

The attack apparently targeted a militant hideout.

The U.S. military in Afghanistan routinely offers no comment on reported cross-border strikes, which are normally launched from unmanned drones. But the United States is the only country operating in the region known to have the capability to launch missiles from drones, which are controlled remotely.